The present invention relates generally to the field of archery products. More specifically, the present invention relates to devices which enhance the impact force of an arrow in response to a target strike.
The impact force of an arrow when it strikes its target is dependent upon its kinetic energy in flight which is generally a function of the arrow mass and the speed at which the arrow travels. In more specific terms, the kinetic energy (Ek, ft-lb) of the arrow is equal to its mass (m, lbs) times the square of the arrow""s velocity (V, ft/sec) divided by twice the acceleration due to gravity (g, ft/sec2)xe2x80x94namely Ek=mV2/2g. The mass of the arrow, however, should not be increased significantly as it would alter its flight characteristics. To increase the speed of the arrow, however, necessitates altering the bow configuration.
It would therefore be highly desirable if arrows were provided with a means by which their kinetic energy could be enhanced without substantially increasing the arrow weight thereby avoiding significantly adverse effects on the arrow""s flight characteristics. It is towards providing such a need that the present invention is directed.
Broadly, the present invention is embodied in a device which significantly increases an arrow""s kinetic energy, and hence the force on target impact, without a substantial decrease in the arrow""s velocity during flight as compared to the same arrow without such a device. In especially preferred forms, the present invention is embodied in an impact-enhancing device which is insertable into an arrow shaft and includes an impact-enhancer weight which is freely moveable within the arrow shaft. The impact-enhancer weight will thus be propelled in response to rapid deceleration of the arrow (i.e., caused by the arrow head striking a target area). The relatively high velocity movement of the impact-enhancer weight will create a secondary kinetic energy effect which drives the arrow head further into the target area. That is, the impact-enhancer weight will be propelled forwardly at a sufficiently high velocity and strike a rearward region adjacent the arrow head thereby generating a secondary impact force (i.e., secondary to the initial target impact of the arrow itself) causing the arrow head to penetrate deeper into the target area. In such a manner, the effect of the arrow head is enhanced.
These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.